Device and Method for Spraying Mold-Releasing Agent

ABSTRACT

A device for spraying a mold-releasing agent and a method therefor is provided by which a sticker and a defective drawing of a mold are prevented from occurring by detecting a leak of the mold-releasing agent, a clogging of a nozzle for spraying the mold-releasing agent, or a failure of a piece of equipment of the device for spraying the mold-releasing agent, to properly control the volume of the sprayed mold-releasing agent. A device  1  for spraying a mold-releasing agent that sprays a mold-releasing agent A on a pattern plate  20  in a molding machine that forms molds from molding sand S by using a flask  10  and the pattern plate  20 , comprising a nozzle  30  for spraying the mold-releasing agent that sprays the mold-releasing agent A on the pattern plate  20 , a piping  40  for supplying the mold-releasing agent that supplies the mold-releasing agent A to the nozzle  30  for spraying the mold-releasing agent, a flow sensor  42  that measures a flow rate of the mold-releasing agent A that flows in the piping  40  for supplying the mold-releasing agent, and a controller  90  that detects a leak of the mold-releasing agent A, a clogging of the nozzle  30  for spraying the mold-releasing agent, or a failure of a piece of equipment of the device  1  for spraying the mold-releasing agent, based on the measured flow rate.

TECHNICAL FIELD

The present invention relates to a device for spraying a mold-releasing agent on a pattern plate in a molding machine that forms molds from molding sand by using a flask and the pattern plate, and a method therefor.

BACKGROUND ART

Conventionally, it has been known that a mold-releasing agent is sprayed in a molding space that is formed by a molding machine to prevent molding sand from adhering to a pattern plate and smoothly carry out drawing a mold (for example, see Patent Literature 1).

However, if the volume of the mold-releasing agent that is sprayed is not appropriate, a problem, such as a sticker (adhesion of molding sand to a pattern plate) or a defective drawing of a mold, occurs. So, controlling the volume of the agent to spray is important. However, the volume has conventionally been adjusted by observing it. Thus, often a change of the volume that is sprayed due to a clogging of a nozzle is not found. This is a problem. Further, leaking of the mold-releasing agent from a piping route or from a spray for the mold-releasing agent is not found. This is also a problem.

Thus, the object of the present invention is to provide a device for spraying a mold-releasing agent and a method therefor by which a sticker and a defective drawing of a mold are prevented from occurring by searching for a leak of the mold-releasing agent, for a clogging of a nozzle for spraying the mold-releasing agent, or for a failure of a piece of equipment of the device for spraying the mold-releasing agent, to properly control the volume of the sprayed mold-releasing agent.

PRIOR-ART PUBLICATION

Patent Literature

[Patent Literature 1]

Japanese Utility Model Registration No. 2535076

SUMMARY OF INVENTION

To achieve the object, a device for spraying a mold-releasing agent of a first aspect of the present invention is, for example, as in FIGS. 1 and 2, a device 1 for spraying a mold-releasing agent that sprays a mold-releasing agent A on a pattern plate 20 in a molding machine that forms molds from molding sand S by using a flask 10 and the pattern plate 20. The device 1 for spraying the mold-releasing agent comprises a nozzle 30 for spraying the mold-releasing agent that sprays the mold-releasing agent A on the pattern plate 20. It also comprises a piping 40 for supplying the mold-releasing agent that supplies the mold-releasing agent A to the nozzle 30 for spraying the mold-releasing agent. It also comprises a flow sensor 42 that measures a flow rate of the mold-releasing agent A that flows in the piping 40 for supplying the mold-releasing agent. It also comprises a controller 90 that searches for a leak of the mold-releasing agent A, for a clogging of the nozzle 30 for spraying the mold-releasing agent, or for a failure of a piece of equipment of the device 1 for spraying the mold-releasing agent, based on the measured flow rate.

By this configuration, the device for spraying the mold-releasing agent comprises the flow sensor that measures the flow rate of the mold-releasing agent that flows in the piping for supplying the mold-releasing agent that is configured to supply the mold-releasing agent to the nozzle for spraying the mold-releasing agent and comprises the controller that searches for a leak of the mold-releasing agent, for a clogging of the nozzle for spraying the mold-releasing agent, or for a failure of a piece of the equipment of the device for spraying the mold-releasing agent, based on the measured flow rate. Thus, a leak of the mold-releasing agent, a clogging of the nozzle for spraying the mold-releasing agent, or a failure of a piece of the equipment of the device for spraying the mold-releasing agent can be searched for based on the flow rate of the mold-releasing agent, to properly control the volume of the sprayed mold-releasing agent.

The device for spraying the mold-releasing agent of the second aspect of the present invention, for example, as in FIG. 2, further comprises a piping 32 for supplying gas that is configured to supply to the nozzle 30 for spraying the mold-releasing agent gas G1 that is used for spraying the mold-releasing agent A. It also comprises a pressure sensor 34 that measures a pressure of the gas G1 that flows in the piping 32 for supplying the gas. The controller 90 searches for a leak of the gas G1, for a clogging of the nozzle 30 for spraying the mold-releasing agent, or for a failure of a piece of the equipment of the device 1 for spraying the mold-releasing agent, based on the measured pressure. By this configuration, the device for spraying the mold-releasing agent comprises the pressure sensor that measures the pressure of the gas that flows in the piping for supplying the gas that is configured to supply the gas that is used for spraying the mold-releasing agent and comprises the controller that searches for a leak of the gas, for a clogging of the nozzle for spraying the mold-releasing agent, or for a failure of a piece of the equipment of the device for spraying the mold-releasing agent, based on the measured pressure. Thus, a leak of the gas, a clogging of the nozzle for spraying the mold-releasing agent, or a failure of a piece of the equipment of the device for spraying the mold-releasing agent can be searched for based on the pressure of the gas, to properly control the volume of the sprayed mold-releasing agent.

The device for spraying the mold-releasing agent of the third aspect of the present invention, for example, as in FIG. 2, further comprises a tank 44 for storing the mold-releasing agent that stores the mold-releasing agent A. It also comprises a device 49 for supplying pressurized air that supplies pressurized air G2 to the tank 44 for storing the mold-releasing agent, to supply the mold-releasing agent A to the nozzle 30 for spraying the mold-releasing agent through the piping 40 for supplying the mold-releasing agent. By this configuration, the device for spraying the mold-releasing agent further comprises the tank for storing the mold-releasing agent that stores the mold-releasing agent and the device for supplying the pressurized air that supplies the pressurized air to the tank for storing the mold-releasing agent, to supply the mold-releasing agent to the nozzle for spraying the mold-releasing agent through the piping for supplying the mold-releasing agent. Thus, the mold-releasing agent can be definitely supplied to the nozzle for spraying the mold-releasing agent by means of the pressurized air.

By the device for spraying the mold-releasing agent of the fourth aspect of the present invention, the controller 90 adjusts a period of time to spray the mold-releasing agent A from the nozzle 30 for spraying the mold-releasing agent, based on the measured flow. By this configuration, since the controller adjusts a period of time to spray the mold-releasing agent from the nozzle for spraying the mold-releasing agent based on the measured flow, the volume of the sprayed mold-releasing agent can be properly controlled.

The device for spraying the mold-releasing agent of the fifth aspect of the present invention, for example, as in FIG. 4, further comprises a laser sensor 60 that detects the mold-releasing agent A that is being sprayed from the nozzle 30 for spraying the mold-releasing agent. By this configuration, since the device for spraying the mold-releasing agent further comprises the laser sensor that detects the mold-releasing agent that is being sprayed from the nozzle for spraying the mold-releasing agent, the mold-releasing agent can be checked to see if it is being properly sprayed.

To achieve the above-mentioned object, a method for spraying a mold-releasing agent of a sixth aspect of the present invention is, for example, as in FIGS. 1, 2, and 3, the method for spraying the mold-releasing agent A on a pattern plate 20 from a nozzle 30 for spraying the mold-releasing agent in a molding machine that forms molds from molding sand S by using a flask 10 and the pattern plate 20. The method comprises a step S10 of supplying the mold-releasing agent A to the nozzle 30 for spraying the mold-releasing agent. It also comprises a step S50 of spraying the mold-releasing agent A on the pattern plate 20 from the nozzle 30 for spraying the mold-releasing agent. It also comprises a step S20 of measuring a flow of the mold-releasing agent A that is supplied. It also comprises a step S202, S204, S206, S220, S222, S224, or S242 of searching for a leak of the mold-releasing agent A, for a clogging of the nozzle 30 for spraying the mold-releasing agent, or for a failure of a piece of equipment for spraying the mold-releasing agent A, based on the measured flow rate.

By this configuration, the method for spraying the mold-releasing agent comprises the step of searching for a leak of the mold-releasing agent, for a clogging of the nozzle for spraying the mold-releasing agent, or for a failure of a piece of the equipment for spraying the mold-releasing agent based on the measured flow rate by measuring a flow rate of the mold-releasing agent that is supplied to be sprayed on the pattern plate from the nozzle for spraying the mold-releasing agent. Thus, the volume of the sprayed mold-releasing agent can be properly controlled.

The method for spraying the mold-releasing agent of a seventh aspect of the present invention, for example, as in FIGS. 2 and 3, comprises a step S30 of supplying gas G1 that is used for spraying the mold-releasing agent A to the nozzle 30 for spraying the mold-releasing agent. It also comprises a step S40 of measuring a pressure of the gas G1. It also comprises a step S100, S120, or S130 of searching for a leak of the gas G1, for a clogging of the nozzle 30 for spraying the mold-releasing agent, or for a failure of a piece of the equipment, based on the measured pressure. By this configuration, the pressure of the gas that is used for spraying the mold-releasing agent is measured as it flows in the piping for supplying the gas that is configured to supply the gas. Based on the measured pressure a leak of the gas, a clogging of the nozzle for spraying the mold-releasing agent, or a failure of the equipment of the device for spraying the mold-releasing agent, is searched for. Thus, the volume of the sprayed mold-releasing agent can be properly controlled.

The method for spraying the mold-releasing agent of an eighth aspect of the present invention, for example, as in FIG. 3, further comprises a step S300 of adjusting a period of time to spray the mold-releasing agent A from the nozzle 30 for spraying the mold-releasing agent, based on the measured flow rate. By this configuration, since the method comprises the step of adjusting the period of time to spray the mold-releasing agent from the nozzle for spraying the mold-releasing agent based on the measured flow rate, the volume of the sprayed mold-releasing agent can be properly controlled.

By the method for spraying the mold-releasing agent of a ninth aspect of the present invention, for example, as in FIG. 4, in the step S50 of spraying the mold-releasing agent the mold-releasing agent A is sprayed on the pattern plate 20 from the nozzle 30 for spraying the mold-releasing agent while the nozzle 30 for spraying the mold-releasing agent is moved. By this configuration, since the mold-releasing agent is sprayed on the pattern plate while the nozzle for spraying the mold-releasing agent is moved, the mold-releasing agent is sprayed on a wide area of the pattern plate.

By the present invention, a leak of the mold-releasing agent, a clogging of the nozzle for spraying the mold-releasing agent, or a failure of the equipment of the device for spraying the mold-releasing agent, can be searched for based on the flow rate of the mold-releasing agent. Thus, the volume of the sprayed mold-releasing agent is properly controlled, to prevent a sticker or a defective drawing of a mold from occurring.

The basic Japanese patent application, No. 2018-066496, filed Mar. 30, 2018, is hereby incorporated by reference in its entirety in the present application.

The present invention will become more fully understood from the detailed description given below. However, the detailed description and the specific embodiments are only illustrations of the desired embodiments of the present invention, and so are given only for an explanation. Various possible changes and modifications will be apparent to those of ordinary skill in the art on the basis of the detailed description.

The applicant has no intention to dedicate to the public any disclosed embodiment. Among the disclosed changes and modifications, those which may not literally fall within the scope of the present claims constitute, therefore, a part of the present invention in the sense of the doctrine of equivalents.

The use of the articles “a,” “an,” and “the” and similar referents in the specification and claims are to be construed to cover both the singular and the plural form of a noun, unless otherwise indicated herein or clearly contradicted by the context. The use of any and all examples, or exemplary language (e.g., “such as”) provided herein is intended merely to better illuminate the invention, and so does not limit the scope of the invention, unless otherwise stated.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a cross-sectional side view illustrating the main part of an exemplary molding machine that has a device for spraying a mold-releasing agent.

FIG. 2 is a block diagram of an embodiment to supply a mold-releasing agent and a gas that is used for spraying the mold-releasing agent in the device for spraying the mold-releasing agent.

FIG. 3 is a flowchart of an exemplary method to search for a leak of the mold-releasing agent or the gas, for a clogging of the nozzle for spraying the mold-releasing agent, or for a failure of the equipment of the device for spraying the mold-releasing agent, based on the flow rate of the mold-releasing agent or the pressure of the gas that is used for spraying the mold-releasing agent. Incidentally, one flowchart is divided into two sheets, i.e., (a) and (b).

FIG. 4 is a cross-sectional side view illustrating the main part of a molding machine, which is a modification of one as in FIG. 1. In it the mold-releasing agent is sprayed while the nozzle for spraying the mold-releasing agent is moved. It has a laser sensor that detects the mold-releasing agent that is being sprayed.

DESCRIPTION OF EMBODIMENTS

Below the embodiments of the present invention are discussed with reference to the drawings. In the drawings, the same or corresponding members are denoted by the same reference numbers. Thus, duplicate descriptions are omitted. First, with reference to FIG. 1, a flask 10, a pattern plate 20, etc., in a molding machine that manufactures molds are discussed. FIG. 1 is a cross-sectional side view illustrating the main part of the molding machine. This main part includes the flask 10, an auxiliary flask 12, a frame 16, the pattern plate 20, a carrier 22 for a pattern, a squeezing member 54, a hopper 50 for molding sand, etc. Here, the pattern plate 20 includes a match plate that is used for simultaneously manufacturing a cope and a drag. Though a molding machine for manufacturing molds with flasks is below discussed, the present invention can be applied to a flaskless molding machine.

In the molding machine the pattern plate 20 is placed on the carrier 22 for a pattern. The flask 10 and the auxiliary flask 12 are stacked in this order on the frame 16 that surrounds the pattern plate 20. The frame 16 is vertically moved by means of a vertical cylinder, which is not shown, through a guide pin 18 that is inserted into an aperture that is formed in the carrier 22 for a pattern. The squeezing member 54 is inserted inside the auxiliary flask 12 from above it. The space that is surrounded by the pattern plate 20, the frame 16, the flask 10, the auxiliary flask 12, and the squeezing member 54, is a molding space.

The hopper 50 for the molding sand is provided above the auxiliary flask 12. It stores the molding sand S and supplies it to the molding space through a nozzle 52 for filling the molding sand that is provided at the lower part. The molding sand S is supplied to the hopper 50 for the molding sand through a chute 56 for supplying the molding sand that is provided to the upper part.

When the molding space is filled with the molding sand S, the hopper 50 for the molding sand and the squeezing member 54 are lowered to squeeze the molding sand S with the pattern plate 20 in the inner space of the flask 10, to thereby manufacture a mold (not shown). At that time, if the frame 16 is lowered, the molding sand S is squeezed from the side of the pattern plate 20. Thus, the molding sand is uniformly squeezed, to form a mold. Then, the hopper 50 for the molding sand and the squeezing member 54 are elevated, so that the mold and the squeezing member 54 are separated. The auxiliary flask 12 is also elevated. After the frame 16 is elevated so that the mold and the pattern plate 20 are separated, the flask 10 is further elevated. The mold that has been manufactured is sent to a next process while it is held by the flask 10.

To facilitate the separation of the mold and the pattern plate 20, a mold-releasing agent A is sprayed on the pattern plate 20 in the state as in FIG. 1. The mold-releasing agent A may be a commercially available mold-releasing agent, which is oil-based, water-soluble, etc. In this embodiment a slit 14 is formed to penetrate the entire auxiliary flask 12. A nozzle 30 for spraying the mold-releasing agent is inserted into the slit 14. The mold-releasing agent A is sprayed from the nozzle 30 for spraying the mold-releasing agent into the molding space. Since the mold-releasing agent A is sprayed into the molding space, which is surrounded by the pattern plate 20, the frame 16, the flask 10, the auxiliary flask 12, and the squeezing member 54, it is prevented from scattering into the atmosphere. Thus, this way is environmentally and economically preferable. Since the nozzle 30 for spraying the mold-releasing agent is located in the auxiliary flask 12, it does not disrupt the squeezing member 54 to squeeze the molding sand S when molding. In the drawing, the nozzle 30 for spraying the mold-releasing agent is horizontally placed. However, it may be downwardly slanted to face the pattern plate 20. The position to place the nozzle 30 for spraying the mold-releasing agent is not limited to that discussed above. It may be a position where the mold-releasing agent A is sprayed on the pattern plate 20, such as in the squeezing member 54.

FIG. 2 illustrates an exemplary block diagram of a device 1 for spraying the mold-releasing agent that sprays the mold-releasing agent A from the nozzle 30 for spraying the mold-releasing agent. In addition to the nozzle 30 for spraying the mold-releasing agent, the device 1 for spraying the mold-releasing agent has a tank 44 for storing the mold-releasing agent that stores the mold-releasing agent A and a controller 90 that controls the spraying of the mold-releasing agent A. It also has a piping 40 for supplying the mold-releasing agent that is configured to supply the mold-releasing agent A from the tank 44 for storing the mold-releasing agent to the nozzle 30 for spraying the mold-releasing agent and a piping 32 for supplying gas that supplies gas G1 that is used for spraying the mold-releasing agent A to the nozzle 30 for spraying the mold-releasing agent. It also has a piping 46 for the pressurized air that is used for supplying the mold-releasing agent (below, also called “the piping 46 for the pressurized air”), which piping supplies pressurized air G2 to the tank 44 for storing the mold-releasing agent. The pressurized air G2 is used for supplying the mold-releasing agent A from the tank 44 for storing the mold-releasing agent to the nozzle 30 for spraying the mold-releasing agent. As discussed above, since the mold-releasing agent A is supplied to the nozzle 30 for spraying the mold-releasing agent by means of the pressure that is generated by supplying the pressurized air G2 to the tank 44 for storing the mold-releasing agent, the mold-releasing agent A can definitely, i.e., at a constant flow rate, be supplied to the nozzle 30 for spraying the mold-releasing agent. However, a means other than the pressure generated by the pressurized air G2 may be used to supply the mold-releasing agent A from the tank 44 for storing the mold-releasing agent to the nozzle 30 for spraying the mold-releasing agent. For example, a gravity flow or a pump may be used. Incidentally, the gas G1 that is used for spraying the mold-releasing agent A from the nozzle 30 for spraying the mold-releasing agent may be air. The pressurized air G2 that is used for supplying the mold-releasing agent A from the tank 44 for storing the mold-releasing agent to the nozzle 30 for spraying the mold-releasing agent may be a gas other than air, for example, an inert gas, such as a nitrogen gas. The gas G1 and the pressurized air G2 are supplied from a source of the gas and a source of the pressurized air, respectively, which are not shown.

A flow sensor 42 that measures the flow rate of the mold-releasing agent A to be supplied to the nozzle 30 for spraying the mold-releasing agent is provided to the piping 40 for supplying the mold-releasing agent. A pressure sensor 34 that measures the pressure of the gas G1 that is supplied to the nozzle 30 for spraying the mold-releasing agent is provided to the piping 32 for supplying the gas. A pressure sensor 48 that measures the pressure of the pressurized air G2 that is used to supply the mold-releasing agent A from the tank 44 for storing the mold-releasing agent to the nozzle 30 for spraying the mold-releasing agent is provided to the piping 46 for the pressurized air. Incidentally, the piping 46 for the pressurized air, the pressure sensor 48, the source of the pressurized air (not shown), etc., constitute a device 49 for supplying the pressurized air. The source of the pressurized air (not shown) may be a compressor or a blower. It may be a pressurized tank, a bottle, etc., that stores the pressurized air that is supplied from a facility outside the device. The data measured by the flow sensor 42, the pressure sensor 34, and the pressure sensor 48 are sent to the controller 90 through a cable 92. The flow sensor 42, the pressure sensor 34, and the pressure sensor 48 may be connected to the controller 90 by radio, but not by the cable 92. The controller 90 may control the operations of the device 1 for spraying the mold-releasing agent, which includes the device 49 for supplying the pressurized air, the source of the pressurized air, etc. It may be a dedicated controller, may be a personal computer, may be incorporated in the controller of the molding machine, or may be incorporated in the controller of any other device or system. It may be located far away from the molding machine.

Next, with reference to FIG. 3, methods for operating the device 1 for spraying the mold-releasing agent and for searching for a failure are discussed. FIG. 3 is a flowchart of an exemplary method for searching for a leak of the mold-releasing agent A or the gas G1, a clogging of the nozzle 30 for spraying the mold-releasing agent, or a failure of a piece of equipment of the device 1 for spraying the mold-releasing agent, based on the flow rate of the mold-releasing agent A and the pressure of the gas G1. One flowchart is divided into two sheets, i.e., (a) and (b). The connecting points are shown by using the encircled numbers, 1-5. First, the source of the pressurized air (not shown) is activated to supply the pressurized air G2 to the tank 44 for storing the mold-releasing agent through the piping 46 for the pressurized air. At that time, the pressure of the pressurized air G2 that flows in the piping 46 for the pressurized air is measured by means of the pressure sensor 48 for the mold-releasing agent that is being supplied, so that the data on the pressure is sent to the controller 90. By supplying the pressurized air G2 to the tank 44 for storing the mold-releasing agent, the pressure inside the tank 44 for storing the mold-releasing agent increases, to push out the mold-releasing agent A. Incidentally, no pressure sensor 48 for the mold-releasing agent that is being supplied needs to be provided. No pressure of the pressurized air G2 needs to be measured. The tank 44 for storing the mold-releasing agent may be a tank that has a publicly-known structure in so far as it can store the liquid mold-releasing agent A and discharge it by means of the pressurized air. The mold-releasing agent A flows from the tank 44 for storing the mold-releasing agent to the nozzle 30 for spraying the mold-releasing agent through the piping 40 for supplying the mold-releasing agent. The process up to this point is a step S10 for supplying the mold-releasing agent A. At this time, the flow rate of the mold-releasing agent A that flows through the piping 40 for supplying the mold-releasing agent is measured by means of the flow sensor 42, so that the data on the flow rate is sent to the controller 90 (a step S20). Incidentally, the source of the pressurized air (not shown) may be a compressor or a blower, or a pressurized tank, a bottle, etc., that stores the pressurized air that is supplied from a facility outside the device.

A source of the gas (not shown) is activated to supply the gas G1 to the nozzle 30 for spraying the mold-releasing agent through the piping 32 for supplying the gas. The gas G1 is used to spray the mold-releasing agent A from the nozzle 30 for spraying the mold-releasing agent. This is a step S30 for supplying the gas that is used for spraying the mold-releasing agent. At that time, the pressure of the gas G1 that flows through the piping 32 for supplying the gas is measured by means of the pressure sensor 34, so that the data on the pressure is sent to the controller 90 (a step S40). Incidentally, the source of the gas may be a compressor or a blower, or a pressurized tank, a bottle, etc., that stores the pressurized air that is supplied from a facility outside the device. Further, the source of the gas may be the same as the source of the pressurized air (not shown). If they are the same, the pressure of the pressurized air G2 to be supplied to the tank 44 for storing the mold-releasing agent is decreased below the pressure of the gas G1 that is used for spraying the mold-releasing agent A from the nozzle 30 for spraying the mold-releasing agent by providing a pressure-reducing valve (not shown), etc., to the piping 46 for the pressurized air.

By supplying the mold-releasing agent A at a set flow rate and the gas G1 at a set pressure to the nozzle 30 for spraying the mold-releasing agent, the mold-releasing agent A is sprayed from the nozzle 30 for spraying the mold-releasing agent on the pattern plate 20. Incidentally, when the wording “be sprayed on the pattern plate 20” is used, the mold-releasing agent A that is sprayed from the nozzle 30 for spraying the mold-releasing agent must not be directed toward the pattern plate 20, but it may reach the pattern plate 20. For example, it may drift in the molding space, to drop on the pattern plate 20.

Now, the method for searching for a leak of the gas G1, for a clogging of the nozzle 30 for spraying the mold-releasing agent, or for a failure of a piece of equipment of the device 1 for spraying the mold-releasing agent, based on the pressure of the gas G1, is discussed. First, the pressure of the gas G1 that has been measured by the pressure sensor 34 is judged to see if it is within a set range (a step S100). The set range of the pressure may be, for example, 0.1 MPa-0.2 MPa. However, it varies depending on the structure of the nozzle 30 for spraying the mold-releasing agent, the property, such as the viscosity of the mold-releasing agent A, etc. If the pressure of the gas G1 is within the set range, the operation is determined to be normal (a step S110).

If the pressure of the gas G1 is lower than the set range, the failure of a piece of equipment of the device 1 for spraying the mold-releasing agent, such as a failure of the source of the gas, of the nozzle 30 for spraying the mold-releasing agent, or of the piping 32 for supplying the gas, is considered to have occurred. Thus, typically an operator searches for the failure (a step S120). Based on the search, a measure to remedy the failure is carried out (a step S290).

If the pressure of the gas G1 is greater than that given in the set range, a clogging of the nozzle 30 for spraying the mold-releasing agent is considered to have occurred (a step S130). Thus, a measure to remedy any failure, i.e., the clogging, is carried out (the step S290).

It is judged if the mold-releasing agent A is to be sprayed from the nozzle 30 for spraying the mold-releasing agent (a step S200). It is judged if the controller 90 sends an order to spray it. Alternatively, an operator may select the order by a touch panel. If it is to be sprayed, it is judged if the flow rate of the mold-releasing agent A that has been measured by the flow sensor 42 is equal to, or greater than, a set flow rate (a step S220). The set flow rate varies depending on the size of the pattern plate 20, the property of the mold-releasing agent A, the structure of the nozzle 30 for spraying the mold-releasing agent, etc. If the flow rate of the mold-releasing agent A is equal to, or greater than, the set flow rate, it is judged if the flow rate is detected only when the order to spray it is sent (a step S240). If the flow rate is detected only when the order to spray it is sent, the operation is determined to be normal (a step S260).

If it is judged by the step S200 not to spray it, then it is judged if the flow rate of the mold-releasing agent A is detected by the flow sensor 42 (a step S202). If no flow rate of the mold-releasing agent A is detected (“not detected” in the step S202), the operation is determined to be normal (a step S210). If the flow rate of the mold-releasing agent A is detected, the position of the leakage of the liquid is determined (a step S204). For example, an operator visually checks the device 1 for spraying the mold-releasing agent. If a leakage of a liquid is found, a measure to remedy the failure, i.e., the position of the leakage of the liquid, is carried out (the step S290). If no leakage of the liquid is found, a failure of instruments, the piping 40 for supplying the mold-releasing agent, etc., is searched for (a step S206). Based on the result of the search, a measure to remedy the failure of instruments, the piping 40 for supplying the mold-releasing agent, etc., is carried out (the step S290).

If the flow rate of the mold-releasing agent A is judged by the step S200 to be less than the set flow rate, it is judged if there is a clogging of the nozzle 30 for spraying the mold-releasing agent or a failure of a piece of equipment of the device 1 for spraying the mold-releasing agent, such as an on-off valve to open and close the piping 40 for supplying the mold-releasing agent or the piping 46 for the pressurized air (a step S222). If it is judged that there is a clogging of the nozzle 30 for spraying the mold-releasing agent or a failure of a piece of equipment of the device 1 for spraying the mold-releasing agent, a measure to remedy the clogging of the nozzle 30 for spraying the mold-releasing agent or the failure of a piece of equipment of the device 1 for spraying the mold-releasing agent is carried out (the step S290). If it is judged that there is none, a failure of instruments is considered to have occurred. Thus, the instruments are checked (a step S224). Then, a measure to remedy the failure of the instruments is carried out (the step S290).

If a flow rate of the mold-releasing agent A is detected when no order to spray it is sent at the step S240, a liquid leakage from the nozzle 30 for spraying the mold-releasing agent, the piping 40 for supplying the mold-releasing agent, etc., is considered to have occurred (a step S242). Thus, a measure to remedy the failure of the nozzle 30 for spraying the mold-releasing agent, the piping 40 for supplying the mold-releasing agent, etc., is carried out (the step S290).

After the measure to remedy the failure has been carried out at the step S290, the operation is repeated from the step S10 for supplying the mold-releasing agent A. When the operation has been judged to be normal after judging both the flow rate of the mold-releasing agent A and the pressure of the gas G1, i.e., at the Step S110 and the step S210 or S260, the operation is repeated from the step S10 for supplying the mold-releasing agent A, though it is not shown in FIG. 3. Incidentally, if required, the period of time to spray the mold-releasing agent A may be adjusted (a step S300).

At the step S300 for adjusting the period of time to spray the mold-releasing agent A, it is adjusted based on the flow rate of the mold-releasing agent A that has been measured by means of the flow sensor 42. That is, a volume of the mold-releasing agent A to be sprayed on the pattern plate 20 is a value that is calculated by multiplying the period of time to spray it by the flow rate of it. Thus, the period of time is adjusted, so that an appropriate volume of the mold-releasing agent A is sprayed on it.

The steps that are discussed above are generally carried out by the controller 90. However, the steps S120, S204, S206, S224, and S242 and the measures (the step S290) are generally carried out by an operator. However, the present invention is not limited to this way.

As discussed above, by the device 1 for spraying the mold-releasing agent, a leak of the mold-releasing agent A, a leak of the gas G1, a clogging of the nozzle 30 for spraying the mold-releasing agent, or a failure of a piece of equipment (that includes instruments) of the device 1 for spraying the mold-releasing agent, can be searched for based on the flow rate of the mold-releasing agent A measured by the flow sensor 42 or on the pressure of the gas G1 for spraying the mold-releasing agent A measured by the pressure sensor 34. Thus, the volume of the mold-releasing agent can be properly controlled.

In the flowchart of FIG. 3, a failure is searched for to judge if one exists, based on the flow rate of the mold-releasing agent A measured by the flow sensor 42 or the pressure of the gas G1 for spraying the mold-releasing agent A measured by the pressure sensor 34. However, it may be searched for based on both the flow rate of the mold-releasing agent A and the pressure of the gas G1, to increase the reliability of the search. For example, when the mold-releasing agent A is to be sprayed, the pressure of the gas G1 is normal, but no flow of the mold-releasing agent A may be detected. In this situation a failure of the piping 40 for supplying the mold-releasing agent, etc., is considered to have occurred, but a clogging of the nozzle 30 for spraying the mold-releasing agent is not.

In the flowchart of FIG. 3, a failure is searched for based on the flow rate of the mold-releasing agent A measured by the flow sensor 42 and the pressure of the gas G1 for spraying the mold-releasing agent A measured by the pressure sensor 34. However, it may be searched for based only on the flow rate of the mold-releasing agent A or only on the pressure of the gas G1. That is, in the device 1 for spraying the mold-releasing agent as in FIG. 2, no flow sensor 42 may be provided or no pressure sensor 34 may be provided.

With reference to FIG. 4, an exemplary device 1 for spraying the mold-releasing agent that further has a laser sensor 60 that detects the mold-releasing agent A that is being sprayed is discussed. By the molding machine as in FIG. 4, when the auxiliary flask 12 is to be placed on the flask 10, the mold-releasing agent A is sprayed from the nozzle 30 for spraying the mold-releasing agent. That is, while the auxiliary flask 12 is being lowered, namely, while the nozzle 30 for spraying the mold-releasing agent is being lowered, the mold-releasing agent A is sprayed. In this way, when the mold-releasing agent A is sprayed while the nozzle 30 for spraying the mold-releasing agent is being lowered, the mold-releasing agent A is more widely sprayed than when it is sprayed from one position. Thus, the mold-releasing agent A can uniformly be sprayed on a wider area of the pattern plate 20.

The laser sensor 60 is provided outside the auxiliary flask 12 that is moving and between the auxiliary flask 12 and the flask 10. By providing it in this way, the mold-releasing agent A can be prevented from adhering to the lens of the laser sensor 60. Further, even if it were to adhere to the lens, it could be easily wiped off. The laser sensor 60 can detect the mold-releasing agent A that is being sprayed, since the amount of laser rays that are received decreases due to the mold-releasing agent A that is sprayed. Thus, properly spraying the mold-releasing agent A can be checked, so that the reliability that the mold-releasing agent A is properly sprayed on the pattern plate 20 increases. Incidentally, when by the molding machine the pattern plate 20, the flask 10, and the auxiliary flask 12 are stacked, not below the squeezing member 54, but at another location to be transported below the squeezing member 54 by means of a turntable (not shown), the nozzle 30 for spraying the mold-releasing agent and the laser sensor 60 may be located near the turntable. The laser sensor 60 may be located at the auxiliary flask 12. The location of it is not limited.

By the above discussion, one can see that the mold-releasing agent A is supplied to the nozzle 30 for spraying the mold-releasing agent by means of the pressurized air G2 that is used to supply the mold-releasing agent A. At the nozzle 30 for spraying the mold-releasing agent, the mold-releasing agent A is sprayed by means of the gas G1 that is used to spray it and that is supplied separately from the mold-releasing agent A. However, the mold-releasing agent A may be sprayed from the nozzle 30 for spraying the mold-releasing agent by means of the pressurized air G2 that is used to supply the mold-releasing agent A, but not by means of the gas G1 that is used to spray it. In this case, a leak of the mold-releasing agent A, a clogging of the nozzle 30 for spraying the mold-releasing agent, or a failure of a piece of equipment (that includes instruments) of the device 1 for spraying the mold-releasing agent, can be searched for based on the flow rate of the mold-releasing agent A measured by the flow sensor 42. Further, the device 1 for spraying the mold-releasing agent may have no piping 32 for supplying the gas, no pressure sensor 34, etc.

Below, the main reference numbers that are used in the specification and the drawings are listed.

-   1 the device for spraying the mold-releasing agent -   10 the flask -   12 the auxiliary flask -   14 the slit -   16 the frame -   18 the guide pin -   20 the pattern plate -   22 the carrier for a pattern -   30 the nozzle for spraying the mold-releasing agent -   32 the piping for supplying the gas -   34 the pressure sensor -   40 the piping for supplying the mold-releasing agent -   42 the flow sensor -   44 the tank for storing the mold-releasing agent -   46 the piping for the pressurized air that is used for supplying the     mold-releasing agent -   48 the pressure sensor -   49 the device for supplying the pressurized air -   50 the hopper for the molding sand -   52 the nozzle for filling the molding sand -   54 the squeezing member -   56 the chute for supplying the molding sand -   60 the laser sensor -   90 the controller -   92 the cable -   A the mold-releasing agent -   G1 the gas that is used for spraying the mold-releasing agent -   G2 the pressurized air -   S the molding sand 

1. A device for spraying a mold-releasing agent that sprays a mold-releasing agent on a pattern plate in a molding machine that forms molds from molding sand by using a flask and the pattern plate, the device comprising: a nozzle for spraying the mold-releasing agent that sprays the mold-releasing agent on the pattern plate; a piping for supplying the mold-releasing agent that supplies the mold-releasing agent to the nozzle for spraying the mold-releasing agent; a flow sensor that measures a flow rate of the mold-releasing agent that flows in the piping for supplying the mold-releasing agent; and a controller that searches for a leak of the mold-releasing agent, for a clogging of the nozzle for spraying the mold-releasing agent, or for a failure of a piece of equipment of the device for spraying the mold-releasing agent, based on the measured flow rate.
 2. The device for spraying the mold-releasing agent of claim 1, further comprising: a piping for supplying gas that is configured to supply to the nozzle for spraying the mold-releasing agent gas that is used for spraying the mold-releasing agent; and a pressure sensor that measures a pressure of the gas that flows in the piping for supplying the gas, wherein the controller searches for a leak of the gas, for a clogging of the nozzle for spraying the mold-releasing agent, or for a failure of a piece of the equipment of the device for spraying the mold-releasing agent, based on the measured pressure.
 3. The device for spraying the mold-releasing agent of claim 1 or 2, further comprising: a tank for storing the mold-releasing agent that stores the mold-releasing agent; and a device for supplying pressurized air that supplies pressurized air to the tank for storing the mold-releasing agent, to supply the mold-releasing agent to the nozzle for spraying the mold-releasing agent through the piping for supplying the mold-releasing agent.
 4. The device for spraying the mold-releasing agent of claim 1 or 2, wherein the controller adjusts a period of time to spray the mold-releasing agent from the nozzle for spraying the mold-releasing agent, based on the measured flow rate.
 5. The device for spraying the mold-releasing agent of claim 1 or 2, further comprising a laser sensor that detects the mold-releasing agent that is being sprayed from the nozzle for spraying the mold-releasing agent.
 6. A method for spraying a mold-releasing agent on a pattern plate from a nozzle for spraying the mold-releasing agent in a molding machine that forms molds from molding sand by using a flask and the pattern plate, the method comprising the steps of: supplying the mold-releasing agent to the nozzle for spraying the mold-releasing agent; spraying the mold-releasing agent on the pattern plate from the nozzle for spraying the mold-releasing agent; measuring a flow rate of the mold-releasing agent that is supplied; and searching for a leak of the mold-releasing agent, for a clogging of the nozzle for spraying the mold-releasing agent, or for a failure of a piece of equipment for spraying the mold-releasing agent, based on the measured flow rate.
 7. The method for spraying the mold-releasing agent of claim 6, further comprising the steps of: supplying gas that is used for spraying the mold-releasing agent to the nozzle for spraying the mold-releasing agent; measuring a pressure of the gas; and searching for a leak of the gas, for a clogging of the nozzle for spraying the mold-releasing agent, or for a failure of a piece of the equipment, based on the measured pressure.
 8. The method for spraying the mold-releasing agent of claim 6 or 7, further comprising the step of adjusting a period of time to spray the mold-releasing agent from the nozzle for spraying the mold-releasing agent, based on the measured flow rate.
 9. The method for spraying the mold-releasing agent of claim 6 or 7, wherein, in the step of spraying the mold-releasing agent, the mold-releasing agent is sprayed on the pattern plate from the nozzle for spraying the mold-releasing agent while the nozzle for spraying the mold-releasing agent is moved. 